Adding method to create process using LowBox token in sandbox code.

sandbox/win/src/policy_target.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sandbox/win/src/policy_target.h"
 
 #include "sandbox/win/src/crosscall_client.h"
 #include "sandbox/win/src/ipc_tags.h"
 #include "sandbox/win/src/policy_engine_processor.h"
 #include "sandbox/win/src/policy_low_level.h"
@@ skipping 61 matching lines @@
 // called before the actual call to LowerToken.
 NTSTATUS WINAPI TargetNtSetInformationThread(
     NtSetInformationThreadFunction orig_SetInformationThread, HANDLE thread,
     NT_THREAD_INFORMATION_CLASS thread_info_class, PVOID thread_information,
     ULONG thread_information_bytes) {
   do {
     if (SandboxFactory::GetTargetServices()->GetState()->RevertedToSelf())
       break;
     if (ThreadImpersonationToken != thread_info_class)
       break;
-    if (!thread_information)
-      break;
-    HANDLE token;
-    if (sizeof(token) > thread_information_bytes)
-      break;
-
-    NTSTATUS ret = CopyData(&token, thread_information, sizeof(token));
-    if (!NT_SUCCESS(ret) || NULL != token)
-      break;
-
     // This is a revert to self.
     return STATUS_SUCCESS;
   } while (false);
 
   return orig_SetInformationThread(thread, thread_info_class,
                                    thread_information,
                                    thread_information_bytes);
 }
 
 // Hooks NtOpenThreadToken to force the open_as_self parameter to be set to
@@ skipping 16 matching lines @@
     ACCESS_MASK desired_access, BOOLEAN open_as_self, ULONG handle_attributes,
     PHANDLE token) {
   if (!SandboxFactory::GetTargetServices()->GetState()->RevertedToSelf())
     open_as_self = FALSE;
 
   return orig_OpenThreadTokenEx(thread, desired_access, open_as_self,
                                 handle_attributes, token);
 }
 
 }  // namespace sandbox